Glyptothorax maceriatus, a new species of sisorid catfish (Actinopterygii: Siluriformes) from north-eastern India

摘要

Glyptothorax maceriatus, new species, is described from the Meghna-Surma River system in Mizoram, northeast India. It differs from most congeners in the Indian subcontinent in having thoracic adhesive apparatus with a narrow elliptic central depression that is almost enclosed posteriorly by skin ridges. The following combination of characters serve to distinguish it from congeners in the Indian subcontinent: nasal barbel not reaching anterior orbital margin; interorbital distance 27.0-31.4% HL; headlength 23.7-25.3% SL; head depth 12.5-14.2 % SL; thoracic adhesive apparatus with narrow elliptic central depression that is almost enclosed posteriorly by skin ridges (striae) and with single, non-diverging series of striae running along its edges; width of adhesive apparatus 55.8-72.1% its length; unculiferous ridges of adhesive apparatus not extending anteriorly onto gular region; absence of striae on first pectoral- and pelvic-fin elements; pectoral-fin length 20.7-24.9% SL; dorsal-spine length 13.0-17.1% SL; smooth posterior edge of dorsal spine; dorsal-to-adipose distance 17.8-23.6% SL; body depth at anus 11.3-13.8% SL; pelvic-fin length 15.9-19.1 % SL; length of anal-fin base 13.9-16.2% SL; caudal peduncle length 21.4-23.9% SL; and caudal peduncle depth 6.4-7.6% SL (3.1-3.4 times in its length).